Mechanical pencil



May 6, 1930. E. c. TUGGLE MECHANICAL PENCIL INVENTOR EC. BY

ATTORNEY Filed June 2] 1928 Patented May 6, 1930 PATENT OFFICE EDGAR C. TUGGLE, F SHARON, PENNSYLVANIA MECHANICAL PENCIL Application filed June 21,

This invention relates to a mechanical pencil and more particularly to drawing pencils. It is well known that draftsmen require a certain kind of point for use in their work and with an ordinary pencil the attainment and retention of such a point necessitates repeating sharpening of the lead consuming considerable time as well as being annoying.

A primary object of this invention is to overcome these objections and also provide a pencil which will produce at all times lines of uniform width.

Another object is to so construct such a penoil that a thin flat lead may be employed and fed as desired, the sharp edges being taken ofi? to prevent the lead from sticking into the paper.

In carrying out these objects, the invent on is susceptible of a wide range of modification without departing from the spirit or sacr1f icing any of the advantages of the claimed 1nvention; there being shown in the drawings for illustrative purposes a preferred and practical form, in which:

In the accompanying drawings Figure 1 represents a perspective view of a pencil constructed in accordance with this invention Fig. 2 is a vertical longitudinal section the inner face of one of the casing SGCtlOIlS being shown in elevation;

Fig. 3 is a longitudinal section taken n the plane at right angles to that shown in Fig. 2;

Fig. 4 is a transverse section taken on the J line 4 4t of Fig. 3; and

Fig. 5 is a similar view taken on the line 5-5 of Fig. 3.

In the embodiment illustrated the casing 1 is shown which may be of any desired cross sectional contour, being here shown rectangular with the corner edges rounded. This casing 1 is composed of two sections 2 and 3 of any suitable material, preferably of aluminum. Section 2 is made thicker than section 3 in order that the seats 7 and 8 may be 10- 1928. Serial in. 287,073.

cated centrally. These sections are designed to be arranged in superposed relation and each has a longitudinally extending slot therein and section 2 having a slot 5 and section 3 a slot 6 which register when the sections are assembled. These sections are secured together in any suitable manner, preferably being riveted as shown at 4, three pairs of rivets being here shown arranged on opposite sides of the slots in the sections so that when the parts are assembled they will not interfere with the operation of the movable member.

The meeting faces of the sections 2 and 3 are provided with longitudinally extending seats 7 and 8 extending throughout the length i of the casing and opening through the front end thereof and thus form a housing and guide way for the fiat lead 9 which is inserted through the open front end of the casing and which is designed to be projected or fed forward by means now to be described.

Mounted to slide longitudinally in the registering .slots 5 and 6 is a lead feeding and control member 10 here shown in the form of a flat shank member 11 with a head 12 at one end arranged on the outer face of the casing and an enlarged threaded end 13 at the other end arranged on the other side of the casing and which is designed to receive a knurled nut 14 which when loosenedpermits the member 10 to move freely in the slot and when tightened securely clamps it in engagement with the casing. This flat shank member "11 carries a tongue 15 of a size toslip and slide freely in the lead seat of the casing as is shown clearly in Fig. 3 and whichis designed to engage the rear end of the fiat lead 9 when the member 10 is moved forward and projects the lead.

Arranged at the base of the point of the pencil casing adjacent the front end of the slots 5 and 6 is a band-like member 16 .which is secured to the casing in any suitablemannet and forms a finger grip to facilitatethe manipulation of the pencil. This band 16 also forms a stop for the outward movement of the member 10. The front end of the pencil is tapered both in. thickness and Width beyond the band 16 as shown clearly in Figs. 1 and 3 and preferably has the point thereof rounded as is shown clearly in Fig. 2. The rounded lead exit end of the pencil prevents all possibility of the pencil point sticking into the drawing paper.

In the use of the pencil the parts being in the position shown in Figs. 1 and 3 the nut 14 is loosened to permit the member 10 to be moved rearwardly as far as desired according to the length of the lead 9 to be inserted. The lead 9 is then pushed inward from the front end of the casing until it abuts the member or until the front end of the lead is moved into the casing. The member 10 is then moved forward a suiiicient distance to project the writing end of the lead 9 about one-sixteenth of an inch beyond the casing. The nut 14 is then tightened and the pencil is ready for use. It is of course understood as the lead 9 is used up the nut 14 is loosened and the lead projected the desired length. The lead 9 has a close fit within its seat in the casing and friction prevents it from falling out. The tightening up of the nut 14 causes the flat member 11 to move toward the nut and the casing is clamped firmly between the head 12 of the member 11 and the nut 14 and thus hold the tongue 15 from slipping when pressure is applied to the lead in use.

It is of course understood that the casing may be finished in any way desired by nickel plating or otherwise.

Without further description it is thought that the features and advantages of the invention will be readily apparent to those skilled in the art, and it will, of course, he understood that changes in the form, proportion and minor details of construction may be resorted to. without departing from the spirit of the invention or its scope as claimed.

1 claim:

1. A writing implement comprising a pair of opposed similar members arranged longitudinally in contact relation and connected together, the opposed faces of the members having a lead retaining guide extending longitudinally thereof, the members also having opposed longitudinally extending slots which 7 open into the guide, the shank passing through the slots and guide, a lead pusher attached to the shank and adjustable longitudina'lly in the guide, and cooperating clamping means associated with the ends of the shank and engageable with the members upon opposite sides of the slots to hold the shank and lead pusher in longitudinally adjusted positions.

2. In a pencil, a pair of solid columns separatedfor agreater part of their length by a narrowslot I and having a corresponding groove in each opposite wall to form a guide for a lead, a flat shank extending through the slot with means on each end for clamping upon said columns at any point along said slot, and lead pusher connected with the shank.

Signed at Sharon in the county of Mercer and State of Pennsylvania this 14th day of June A. D. 1928.

EDGAR C. TUGGLE. 

